PENTAGON —
The U.S. military says that within the next three years, it will put women in key combat roles from which they were previously excluded.

American women have been serving in combat roles and hundreds have been killed on the front lines for years, but they have been excluded from key positions in areas including Special Operations and infantry.

On Tuesday, officials from all four branches of the U.S. military gathered at the Pentagon to announce a timeline for those changes. The Marines already have come up with new gender-neutral physical tests, and by the middle of 2015, the Army will have new standards that will allow women to be part of its elite Ranger regiment.

U.S. Army Major General Bennet Sacolick was among those making the announcement. He said it is the start of a new era, and he referred to the action film series depicting a U.S. war hero who relies much on his brute strength.

“We're looking for smart, qualified operators. You know, there's a new dynamic. The days of Rambo are over. We're looking for young men that can speak and learn a foreign language and understand culture, that can work with indigenous populations and culturally tuned manners. The defining characteristic of our operators [is] intellect," said Sacolick.

The changes have prompted questions of whether changing standards will diminish military readiness. Among their concerns, critics say having women in tight-knit, high-stress situations will create privacy issues and hurt unit cohesiveness.

Officials on Tuesday said they are fine-tuning their plans before beginning the implementation and looking at models of other countries such as Israel and Canada, which have successfully integrated women into their militaries.

Defense Secretary Chuck Hagel has said he is confident the changes will not diminish the U.S. military's effectiveness.